Fish-tail bit.



H. A. BARDEEN.

FISH TAIL BIT.

APPLICATION FILED NOV. 5. 1913.

Patented Apr. 20, 1915.

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HUGH A. BARDEEN, OF LOS ANGELES, CALIFORNIA, ASSIGNOR 0F ONE-HALF TO RICHARD E. KLINE,

013 LOS ANGELES, CALIFORNIA.

FISH-TAIL BIT.

Application filed November 5, 1913.

To all whom it may concern:

Be it known that I, HUGH A. BARDEEN, a citizen of the United States, residingat Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Improvement in Fish-Tail Bits, of which the following is a specifi cation.

My invention relates to bits, such as are used in drilling oil wells with the so-called rotary system in which the bit is rotated for the purpose of producing the well.

The principal object of my invention is to so improve the ordinary fish tail bit that its efiiciency may be greatly increased.

A further objectis' to produce an improvement in such a bit in which rotating cutters will do the greater part of the work, these cutters being made so that they are readily removable and renewable.

I have found that the ordinary form of fish tail bit as commonly used is quite efiieient, being especially so in that it mixes the softer shales and water in the bottom of the well thus producing a smooth mud which does not have any considerable tendency to cake. I have also found that the greatest amount of wear on such a bit takes place at the outer corners, even in the harder rocks, the central portion of the bit apparently doing little more than to break up the annular core produced by. these outer corners. The flow of the water about this core greatly assists this action.

In my invention I utilize a pair of cylindrical rotating cutters as a substitute for the outer corners of an ordinary fish tail bit and still depend on the central lportion of the bit to'break up the core produced by these out ters. I further make the cutters relatively thin thus cutting a narrow annular groove and leaving a core which takes up the greater portion of the bottom of the hole.- It has been demonstrated that it takes relatively little power to break up such a core, the greaterportion of the power used being expended in cutting the groove. By reducing the face of thecutters to a minimum the width of the groove and the power expended thereon becomes a minimum and the elliciency of the bit becomes a maximum.

Further objects and advantages will appear hereinafter.

Referring to the drawings which are for illustrative purposes only: Figure 1 is a side Specification of Letters Patent.

standard practice a channel Patented a so, rare. Serial No. 799,400.

elevation of one embodiment of my invention partly in section. Fig. 2 is an elevation-at right angles to Fig. l, the well being shown partly in section. Fig. 3 is a plan view of my invention from below, the walls of the well being shown in section.

In these drawings, 10 is the body of a fish tail bit provided with a stem 11 which is threaded as at 12 for the attachment of suitable drilling casing which is supplied with water under pressure according to standard practice in' rotary drilling. Two holes 13 are drilled, as shown, through the shoulders 14: of the bit in such a manner as to force water downwardly over the face thereof. The bottom 15 of the bit is enlarged as shown at 16 and has slots 17 formed therein in each of which is placed a cylindrical cutter 18 which isprovided with cutting teeth as shown at 19. The cutters 18 are suitably hushed as shown' at 20 and turn upon a 'pin 21 which is secured in a counter bored hole 22 in the body 10 'of the bit. The pin 21 may be secured in place by means of a small pin 23 or by any other suitable means. The lower portion of the bit forms cutting edges 24 as plainly shown in the drawings and in accordance with the on the ordinary forms of fish tail bits.

The method of operation of my invention is as follows: The stem 11 being secured to the casing through which water under pressure is kept flowing, this water is forced downwardlv through the openings 13 along the face of the bit which is constantly rotated by the casing. The water is mixed with the cuttings from the bit and forms a smooth mud which is forced upwardly by the water pressure about the outside of the casing. The cutters 18 rotate freely and cut 25 around the outer circumference of the bottom of the well leaving a core 26 projecting upwardly in the center. The channel 25 is relatively narrow and the greater proportion of the material is re moved by the cutting edges 2-1 at the bottom of the bit. These cutting edges do not wear cut an annular groove together with the cutting edges 24 common to fish tail bits for breaking up the annular core, forms a very eificient combination for the desired purpose.

I claim as my invention: 1. A fish tail bit having toothed revolving cutters located on radial bearings at the outer corners of its lower edge.

2. A bit comprising a flat body, a stem by which said body may be rotated, a stationary pin radially placed near each of the lower corners of said bit, and a toothed cutter turning freely on each of said pins, the lower edge of the body intermediate of said cutters having a fish tail form.

3. A fish tail bit having toothed cylindrical cutters turning freely on pins located radially near the lower outer corners of said bit, said cutters projecting slightly below the lower edge of said bit.

4. A fish tail bit comprising a fiat body, a stem by which said body may be rotated, means for introducing water into the well at either side of said flat body, inclined toothed cylindrical cutters at the outer lower corners of said flat body, and cutting edges formed on said flat body between said outters and at a slightly higher elevation than the cutting edges of said cutters.

5. A fish tail bit having cylindrical toothed cutters located at its lower edge with their axes inclined with relation to the bottom of the hole.

6. A fish tail bit comprising a flat body adapted to be secured to the bottom of a r0,- tary drill pipe, and rotating cutters secured on inclined axes with their lower cutting edges near the cutting edge of the bit.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 28th day of October, 1913.

HUGH A. BARDEEN In presence of- FRED A. MANSFIELD, Fem). W Hams. 

